Hanlon's razor is an adage or rule of thumb that states "never attribute to malice that which is adequately explained by stupidity." Known in several other forms, it is a philosophical razor that suggests a way of eliminating unlikely explanations for human behavior. It is likely named after Robert J. Hanlon, who submitted the statement to Murphy's Law Book Two. Similar statements have been recorded since at least the 18th century.
Origin
Inspired by Occam's razor, Hanlon's razor became known as such in 1990 by the Jargon File, a glossary of computer programmer slang, though the phrase itself had been in general usage years before.
Later that same year, the Jargon File editors noted lack of knowledge about the term's derivation and the existence of a similar epigram by William James. In 1996, the Jargon File entry on Hanlon's Razor noted the existence of a similar quotation in Robert A. Heinlein's novella Logic of Empire (1941), with speculation that Hanlon's Razor might be a corruption of "Heinlein's Razor". (The character "Doc" in Heinlein's story described the...